Do you have to replace both o2 sensors when one fails on Toyota sequoia?

When one O2 sensor fails on a Toyota Sequoia, it's not strictly necessary to replace both sensors at the same time. However, if one sensor has failed due to age or wear, the other sensor may soon follow, especially if they are of similar age. Replacing both can prevent future issues and ensure optimal engine performance. It's advisable to consult a mechanic for a thorough diagnosis before making a decision.